Academic Commons Search Resultshttp://academiccommons.columbia.edu/catalog.rss?f%5Bsubject_facet%5D%5B%5D=Geographic+information+science+and+geodesy&q=&rows=500&sort=record_creation_date+desc
Academic Commons Search Resultsen-usAn online operational rainfall-monitoring resource for epidemic malaria early warning systems in Africahttp://academiccommons.columbia.edu/catalog/ac:181411
Grover-Kopec, Emily; Kawano, Mika; Klaver, Robert; Blumenthal, Martin Benno; Ceccato, Pietro N.; Connor, Stephenhttp://dx.doi.org/10.7916/D8WW7G0HMon, 08 Sep 2014 00:00:00 +0000Periodic epidemics of malaria are a major public health problem for many sub-Saharan African countries. Populations in epidemic prone areas have a poorly developed immunity to malaria and the disease remains life threatening to all age groups. The impact of epidemics could be minimized by prediction and improved prevention through timely vector control and deployment of appropriate drugs. Malaria Early Warning Systems are advocated as a means of improving the opportunity for preparedness and timely response. Rainfall is one of the major factors triggering epidemics in warm semi-arid and desert-fringe areas. Explosive epidemics often occur in these regions after excessive rains and, where these follow periods of drought and poor food security, can be especially severe. Consequently, rainfall monitoring forms one of the essential elements for the development of integrated Malaria Early Warning Systems for sub-Saharan Africa, as outlined by the World Health Organization. The Roll Back Malaria Technical Resource Network on Prevention and Control of Epidemics recommended that a simple indicator of changes in epidemic risk in regions of marginal transmission, consisting primarily of rainfall anomaly maps, could provide immediate benefit to early warning efforts. In response to these recommendations, the Famine Early Warning Systems Network produced maps that combine information about dekadal rainfall anomalies, and epidemic malaria risk, available via their Africa Data Dissemination Service. These maps were later made available in a format that is directly compatible with HealthMapper, the mapping and surveillance software developed by the WHO's Communicable Disease Surveillance and Response Department. A new monitoring interface has recently been developed at the International Research Institute for Climate Prediction (IRI) that enables the user to gain a more contextual perspective of the current rainfall estimates by comparing them to previous seasons and climatological averages. These resources are available at no cost to the user and are updated on a routine basis.Geographic information science and geodesy, Epidemiologymbb1, pnc2102, sjc2021International Research Institute for Climate and SocietyArticlesCrowdsourcing in the Quaternary sea level community: insights from the Pliocenehttp://academiccommons.columbia.edu/catalog/ac:164098
Rovere, Alessio; Raymo, Maureen E.; O’Leary, M. J.; Hearty, P. J.http://hdl.handle.net/10022/AC:P:21267Tue, 06 Aug 2013 00:00:00 +0000In order to establish the ‘fingerprint’ of past sea level changes, many field measurements of paleo sea level from globally distributed locations are needed. It is because this problem requires a geographically expansive database that it becomes an ideal candidate for crowdsourcing techniques. In order to crowdsource sea level data from the Mid-Pliocene Warm Period, we developed three tools: PlioWiki, RSLcalc and RSLmap. PlioWiki is a web portal, open to contributions, where investigators can share knowledge on Pliocene to Quaternary relative sea levels. RSLcalc is a standardized, ready-to-use tool for field geologists to log their own sea level field observations and, if they desire, submit new data to an open access database of relative sea level markers. RSLmap allows one to visualize and query the database built with RSLcalc on a Google Map interface. Here we describe these tools and discuss the advantages of crowdsourcing, relative to traditional approaches, for the creation of sea level databases for any time period.Physical oceanography, Geographic information science and geodesyar3170, mer2Lamont-Doherty Earth ObservatoryArticlesDowngrading Recent Estimates of Land Available for Biofuel Productionhttp://academiccommons.columbia.edu/catalog/ac:161183
Schepaschenko, Dmitry; McCallum, Ian; Kraxner, Florian; Schill, Christian; Perger, Christoph; Nalepa, Rachel A.; Velde, Marijn van der; See, Linda; Fritz, Steffen; Cai, Ximing; Zhang, Xiao; Ortner, Simone; Hazarika, Rubul; Cipriani, Anna; Bella, Carlos Di; Rabia, Ahmed H.; Garcia, Alfredo; Vakolyuk, Mar'yana; Singha, Kuleswar; Beget, Maria E.; Erasmi, Stefan; Albrecht, Franziska; Shaw, Brian; Obersteiner, Michaelhttp://hdl.handle.net/10022/AC:P:20343Thu, 16 May 2013 00:00:00 +0000Recent estimates of additional land available for bioenergy production range from 320 to 1411 million ha. These estimates were generated from four scenarios regarding the types of land suitable for bioenergy production using coarse-resolution inputs of soil productivity, slope, climate, and land cover. In this paper, these maps of land availability were assessed using high-resolution satellite imagery. Samples from these maps were selected and crowdsourcing of Google Earth images was used to determine the type of land cover and the degree of human impact. Based on this sample, a set of rules was formulated to downward adjust the original estimates for each of the four scenarios that were previously used to generate the maps of land availability for bioenergy production. The adjusted land availability estimates range from 56 to 1035 million ha depending upon the scenario and the ruleset used when the sample is corrected for bias. Large forest areas not intended for biofuel production purposes were present in all scenarios. However, these numbers should not be considered as definitive estimates but should be used to highlight the uncertainty in attempting to quantify land availability for biofuel production when using coarse-resolution inputs with implications for further policy development.Alternative energy, Land use planning, Geographic information science and geodesyac1116Lamont-Doherty Earth ObservatoryArticlesKinematic Positioning with DGPS: Expanding Frontiers in Aerogeophysicshttp://academiccommons.columbia.edu/catalog/ac:144799
Bell, Robin E.http://hdl.handle.net/10022/AC:P:12636Mon, 20 Feb 2012 00:00:00 +0000Airborne geophysics has long been used for regional studies of remote and inaccessible areas. Recent developments in precise positioning of aircraft with the Global Positioning System (GPS) have greatly expanded the range of previously intractable science problems which now can be addressed with airborne techniques (i.e. Brozena et al, 1992). Differential GPS techniques for modern aerogeophysical studies include both realtime navigation of the aircraft and post-mission recovery of the precise positions for data reduction. Major science problems which have been addressed recently with aerogeophysics include deciphering the dynamics of the world's major ice sheets, imaging surface displacements due to earthquakes and decoding the structure of the continental lithosphere. Airborne studies often recover higher resolution data than can be retrieved with satellite technology. Subsequently the aircraft based approach fills a unique niche where land and ship based operations are expensive, difficult or even impossible.Geographic information science and geodesyreb4Lamont-Doherty Earth ObservatoryArticles